1. Field of Invention
The invention relates to sterilization pouches and more particularly to a self-sealed medical instrument sterilization pouch.
2. Description of Related Art
Medical instruments have to be gathered after use, cleaned, packaged in sterilizable pouches. Medical instruments are sealed in a closed space defined by the pouch walls, and then subjected to a sterilizing environment such as steam or high temperature water vapor used to sterilize the instruments. Besides, the pouch-enclosed instruments are subjected to a sterilizing gas such as ethylene oxide.
The sealed pouches comprise a lower sheet and an upper sheet. The lower sheet is typically planar sheet material, suitably cellulosic in composition and printable, and pervious to steam, water vapor and sterilization gases. The upper sheet is planar, but typically of transparent plastic such as polyester, impervious to water vapor, steam and sterilizing gases. Moreover, to make sure that a given pouch has been sterilized, indicators are used. One way to make sure that a given pouch has been sterilized is to provide a separate indictor-strip into the pouch. Besides, the indicators typically are printing inks having color change response to steam, high temperature water vapor or a sterilizing gas such as ethylene oxide, or other sterilizing agent. For example, the ink permanently changes from gray to brown when exposed to sterilizing conditions.
Conventional sterilizing pouches are formed of sheet material printed with identifying brand names and other information on an outward face, and the indictor ink has been placed on the same face. In addition, in order to protect ink dot from deleterious frictional contact with the medical instruments, a protective barrier is preferably provided between the dot and the medical instruments. The barrier is integrated into a seal line by bifurcating the seal line at the apex thereof to form a diamond-shaped enclosure within which the indictor ink dot is placed.
However, the conventional sterilizing pouches have several drawbacks. First, the conventional sterilizing pouches are lack of protection for the ink from frictional removal during handling and storage. Medical instruments may be contaminated by ink. Second, the separate indictor-strip is easy to be polluted. Finally, the conventional sterilizing pouches have a V-shaped seal line to form the barrier, but the seal line is easy to be breached by the medical instruments during handling and storage. Thus, the need for improvement still exists.